Zipper registration using eye-mark encoder

ABSTRACT

The apparatus uses a servo motor and an accumulator dancer arm to buffer the motion of film, with zipper and clips or sliders already inserted, in a zipper-sealing machine. The servo drives the film to an eye-mark and then stops the film. Upstream of the servo motor, the film and zipper stop so that the zipper can be processed, such as by ultrasonic crush stations and clip insertion stations. Downstream of the servo motor, the film runs out of an accumulator to the bagger/wrapper apparatus.

This application claims priority under 35 U.S.C. §119(e) of provisionalapplication Ser. No. 61/044,563 filed on Apr. 14, 2008, entitled “ZipperRegistration Using Eye-Mark Encoder”.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the manufacture of reclosable packaging andpertains to a method for improving registration when inserting a zipperwith slider clips into packaging film, by use of an eye-mark and anencoder.

2. Description of the Prior Art

The prior art of zipper registration in the manufacture of reclosablepackages and bags is well-developed for its intended purposes. Forexample, commonly-assigned U.S. Pat. No. 7,172,545 entitled“Registration of Intermittently Moved Fastener Tape With ContinuouslyMoving Web” issued on Feb. 6, 2007 to Howell and Wallace discloses anapparatus and method using continuous film motion through thezipper-sealing machine and only the zipper has intermittent motion(stop-starts) with the aid of an accumulation assembly. Related art isdisclosed in US 2006/0207727 entitled “Apparatus for RepeatedlyAdvancing Fastener Tape a Predetermined Distance” filed on Mar. 16, 2005by Cortigiano and US 2008/0134632 entitled “Method of Registering Zipperfor Reclosable Package”, filed on Dec. 6, 2006 by Howell.

Other prior art devices utilize a similar method to accumulate film. Themachine jogs the film and attached zipper using a servo to eye-mark andstop it. Upstream of the stop, an ultrasonic unit stomps the zipper butno clip is inserted. Downstream of the stop, the film with the zipperattached is fed out of an accumulator to the bagger.

However, further improvements are sought in the registration of thezipper, particularly when inserting zipper with clips into packagingfilm.

OBJECTS AND SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provideimprovements in the registration of a zipper in the manufacture ofreclosable packages, particularly when inserting zipper with clips intopackaging film.

It is therefore a further object of the present invention to allow acontinuous motion bagger/wrapper to be coupled with an intermittentmotion zipper-sealing machine.

These and other objects are attained by a method and apparatus whichuses a servo motor and an accumulator dancer arm to buffer a stop-startmotion of film, with the zipper and clips (or sliders) already attached,in the zipper-sealing machine. The servo drives the film to an eye-markand then stops the film. Downstream of the servo motor, film,runs out ofan accumulator to the vertical or horizontal bagger. Upstream of theservo motor, the film and zipper stops so that the zipper can beprocessed, typically by an ultrasonic crush application and a clipapplication.

DESCRIPTION OF THE DRAWINGS

Further objects and advantages of the invention will become apparentfrom the following description and from the accompanying drawings,wherein:

FIG. 1 is a schematic of the zipper sealing portion of the apparatus ofthe present invention.

FIG. 2 is a schematic of the zipper insertion portion of the apparatusof the present invention.

FIG. 3 is a schematic of the eye-mark sensor and accumulator portion ofthe apparatus of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings wherein like numerals refer to likeelements throughout the several views, one sees from FIG. 1 that theapparatus 10 includes spool 12 which serves as a source of zipper 100.Zipper 100 passes over a first accumulator (or unwind dancer) 14 whichincludes idler wheels 16, 18 with fixed axes of rotation and unwinddancer arm 20 which moves vertically (in the illustrated orientation) toaccommodate differences in speed between the zipper 100 being fed fromspool 12 and the zipper I 00 being fed through the downstreamstations—first ultrasonic crush station 22, second ultrasonic crushstation 24, first clip insertion station 26 and second clip insertionstation 28. First and second ultrasonic crush stations 22, 24 applyultrasonic energy to create the ends of the zipper segments, while firstand second clip insertion stations 26, 28 insert the clips (alternatelyreferred to as sliders) which allow the consumer or user to open andclose the resulting zipper segments by separating and interlocking,respectively, the zipper profiles.

As shown in FIG. 2, zipper 100 is then captured by zipper insertion arm30 and sealed to polymeric web or film 200. Film 200 includes periodiceye-marks 202, such as, but not limited to, small rectangular ink markspositioned toward the outer edge of film 200. The eye-marks 202 arepositioned a specific distance apart (such as, but not limited to, apackage width).

As shown in FIG. 3, film 200 (with zipper 100 attached) is scanned byeye-mark sensor 34 and driven by servo motor 36 (and associated drivemechanism 38). Film 200 is then fed through second accumulator 40 whichincludes idler wheels 42, 44 with fixed axes of rotation and anaccumulator dancer arm 46 which moves vertically (in the illustratedorientation) to accommodate differences in speed between the film 200being fed from the zipper insertion arm 30 and being fed to thebagger/wrapper apparatus (not shown), particularly to provide asubstantially constant speed of feeding to the bagger/wrapper apparatus(not shown).

As film 200 passes in front of eye-mark sensor 34 and an eye-mark 202 isdetected, the eye-mark sensor 34 signals servo motor 36 to momentarilystop film 200 upstream of servo motor 36. Zipper 100 is likewise stoppedupstream as it passes through first and second ultrasonic crush stations22, 24 and first and second clip insertion stations 26, 28 therebypermitting the crush and clip insertion operations to be performed on amomentarily stationary zipper. Meanwhile, the operation of the secondaccumulator 40 allows the film 200 (with zipper 100 attached) tocontinuously feed the bagger/wrapper apparatus at a substantiallyconstant speed. After the operations on stationary zipper 100 atstations 22, 24, 26, 28 are completed, the servo motor 36 drives zipper100 and film 200 at a rate fast enough to replenish the secondaccumulator 40. The process then repeats itself, thereby allowing forintermittent motion of the zipper 100 and film 200 while providing acontinuous feed at a substantially constant speed from secondaccumulator 40 to the bagger/wrapper apparatus.

Thus the several aforementioned objects and advantages are mosteffectively attained. Although preferred embodiments of the inventionhave been disclosed and described in detail herein, it should beunderstood that this invention is in no sense limited thereby and itsscope is to be determined by that of the appended claims.

1. A process of manufacturing at least a portion of a reclosable packageincluding the steps of: providing a length of zipper material; providinga station for inserting clips onto the length of zipper material;providing a length of film; sealing the length of zipper material to thelength of film; scanning the film for an eye-mark; and upon detectingthe eye-mark, momentarily stopping the length of zipper material and thelength of film and activating the station for inserting clips onto thelength of zipper material.
 2. The process of claim 1 wherein motion ofthe film and the zipper is momentarily resumed after clips have beeninserted on the length of zipper material.
 3. The process of claim 2wherein the step of providing a length of zipper material is performedby a spool.
 4. The process of claim 3 further including the step ofproviding a first accumulator downstream of the spool whereby the spoolcan continue to provide the length of zipper material during the step ofmomentarily stopping the length of zipper material.
 5. The process ofclaim 4 further including the step of providing a crush station forperforming periodic crush operations on the length of zipper.
 6. Theprocess of claim 5 wherein the periodic crush operations are performedduring the momentary stopping of the length of zipper material.
 7. Theprocess of claim 6 further including the step of driving the film with aservo motor.
 8. The process of claim 7 wherein the step of driving thefilm with a servo motor and the step of momentarily stopping the zipperare responsive to the step of scanning the film for eye-mark.
 9. Theprocess of claim 8 further including the step of providing a secondaccumulator downstream of the servo motor.
 10. The process of claim 9wherein speed of the film and zipper from the second accumulator remainssubstantially constant.
 11. An apparatus for manufacturing at least aportion of a reclosable package including: a source of a length ofzipper material; a station for inserting clips onto the length of zippermaterial; a source of a length of film; a sealer for sealing the lengthof zipper material to the length of film; a scanner for scanning thefilm for an eye-mark; and wherein upon the scanner detecting theeye-mark, the length of zipper material and the length of film aremomentarily stopped and station inserts clips onto the length of zippermaterial.
 12. The apparatus of claim 11 wherein motion of the film andthe zipper is momentarily resumed after clips have been inserted on thelength of zipper material.
 13. The apparatus of claim 12 wherein thesource of a length of zipper material is a spool.
 14. The apparatus ofclaim 13 further including a first accumulator downstream of the spoolwhereby the spool can continue to provide the length of zipper materialwhile the length of zipper material is momentarily stopped.
 15. Theapparatus of claim 14 further including a crush station for performingperiodic crush operations on the length of zipper.
 16. The apparatus ofclaim 15 wherein the periodic crush operations are performed while thelength of zipper material is momentarily stopped.
 17. The apparatus ofclaim 16 further including a servo motor to drive the film.
 18. Theapparatus of claim 17 wherein the servo motor is responsive to thescanner.
 19. The apparatus of claim 18 further including a secondaccumulator downstream of the servo motor.
 20. The apparatus of claim 19wherein speed of the film and zipper from the second accumulator remainssubstantially constant.